I think the Prince CTS oversize racket that is the most readily available, if you don't mind the Synergy series is the Prince CTS Synergy DB26 OS.
If you're wanting the "original" line, the Approach (green - 28mm tip) and Graduate (bluish silver - 26mm tip, graphite/fiberglass) came first, then the addition of the Thunderstick (dark blue - 36mm tip) and Precision (dark purple - 24mm tip, graphite/fiberglass), then the Lighting (gold - 26mm tip). Those frames came out in '88-'90. They were labeled as 90 and 110. In '91 Prince started labeling them as Midplus and Oversize.
In mid-'91 came the Response (26mm tip) which looked like a red Lightning since it had the DB. Then came the Blast (26mm tip) and Storm (32mm tip).
Then in '92 came the Synergy line available in MP and OS. Each labeled by the width at the tip. The DB24 (MP only available in Europe), DB26, 26, 28, and 32.
The reason the Synergy DB26s are the most readily available is because they were made for the longest time. I don't know about the rest of the Synergy frames. The line debuted in '92 but were available until 2000. The other frames of the CTS lineage were only made for a year or two before Prince discontinued them or changed the cosmetics.......I'm familiar with these frames, not some of the extended and other iterations made toward the mid-90s.
Of the original line, I'd have to say the Thunderstick (which might be too unwieldy) and the Approach are the most available still. The Approach comes up on e-bay about one or two times a month. The Synergy DB26 OS has several examples on e-bay as of this post.