Nearly three years ago, Dan Troy sent in $600 to reserve space at the Christian booksellers convention to exhibit his line of sportswear emblazoned with slightly offbeat Christian messages.

"Two years ago we were 30th on the waiting list . . . . Last year we were number one -- right on the edge. I guess the Lord was testing us," Troy said yesterday at the gathering in the Washington Convention Center as he leaned against a rack of T-shirts proclaiming, "Get Saved -- or Else."

The wait paid off. By the close of business Monday, the first day of this year's convention, Troy and his partner had made enough sales to pay all exhibition costs, "including hotel and air fare" from Phoenix, where their Alpha-Omega Design company is based. "The next three days will be gravy," he said.

Troy's company is one of 330 exhibitors crammed into the Convention Center this week in search of part of the $1.27 billion annual gross sales of some 5,500 Christian bookstores across the country.

While the focus of the industry is indeed books, the stores, largely mom and pop operations, have branched out in many directions.

"Today's Christian bookstore is truly a Christian department store," said William R. Anderson, president of the Christian Bookseller's Association, whose convention ends tomorrow.

In addition to books, the Convention Center is awash in greeting cards, games, toys, clothing, jewelry, luggage, wall plaques, coffee mugs, records, cassettes, videotapes, pencils, pens, bumper stickers, paper weights and stained glass -- all bearing religious sentiments.

Praise Unlimited, which sells "Scripture-based praise toys," has a Praise and Worship Bear for $32 -- hug it and it tells you that Jesus loves you.

The Florida-based company also has dolls -- named Faith, Joy, Hope and Love -- who do the same thing, in English or Spanish.

SoulMates offers its "Heavenly Kids" line -- five dolls, each named after a Biblical character and wearing a name tag with the appropriate Biblical story on the reverse side.

And Wee-Win Toys takes the packaged approach to Bible toys that teach: a tape of the story, plus, for example, a sturdy plastic whale with a removable Jonah, for $19.95.

There are all kinds of teaching aids available, from graphically colored flannel-board sets -- "make the Bible stories come alive," says Bette Lukens Inc. -- to an infinite variety of posters and pictures.

For $25, a Sunday School teacher can get a Sermons in Chemistry set. Pour one chemical into a test tube and it turns black as sin. Pour another into a second tube and it becomes red as Christ's blood. Pour Christ's blood into the sin-blackened tube and it is instantly cleansed.

The Bible, in ever-increasing numbers of translations, versions and adaptations, continues to be the backbone of the industry. And it has attracted an endless list of accessories. Bible covers, for example, are available in everything from elegant hand-tooled leather to ruffle-trimmed quilted calico to the "California collection" of sturdy and colorful rip-stop nylon.

The goods on display in the 225,000-square-foot exhibit area of the Convention Center are overwhelmingly keyed to evangelical Protestants. But according to Anderson of the booksellers association, the stores attract growing numbers of Catholics as well.

The organization's research has shown, he said, that "for every 2 1/2 Baptists, one Roman Catholic comes into a Christian bookstore."

According to association statistics, the nationwide average for retail sales by an individual Christian bookstore climbed from $86,700 a decade ago to $235,000 last year.

And the growth is expected to continue. The association's market research has pinpointed the prime targets for local stores as married women aged 26 to 48 and young people aged 16 to 22. According to census figures, association leaders say, both groups are expected to continue to expand for another decade.