They made a few early models BT-100 Golden Clays. They have nice wood and no recoil reducer like the newer 99 GC's. These all were highluster blued barrels with porting. I've heard conflicting stories as to whether fixed choke barrels were ever available, as the only ones I've ever seen had tubes.
The Golden Clays BT-99 isn't really worth the extra $$$ I had one and it actually shot worse than than my old fixed choked models. I wouldn't drop $3K or even $2500 on a used GC golden clays. If you want a real trap gun buy a SBT ljutic or a KX-5. Much better gun for the money. I like BT's but all the GC is a cheap dressed up regular BT99. The comb hardware sucks as with all brownings and the engraving is just rolled. If I were you I'd look for a late 70's BT 99 34" in mint condition. They shoot nice and high and are alot nicer looking and better built. You could easily get a nice one for $1100.