When I went there myself (from MAN) in Dec 94, we were part of a group of 7 and there were three other passengers on a 738 (iirc) with TK.
First B738 delivered to TK on 30.10.1998.
Travelled that route frequently myself during the 90's and the TK flight was rarely less than 80% full. From memory I think the aircraft was a B734.