Despite your lack of historic info, you still have something to help put together a range for him.... Given he has played tight thus far, you can probably discount AJ/KQ/QJ type marginal hands for an UTG raise. You can certainly include TT+. His small raise may also be his way of entering a pot in EP with a small pair - some people won"t open limp in any circumstance.
So - he checked the K hi flop, but might be trapping with AK/AA. Would he really check again on the turn, particularly as the board got wetter.... surely time for a bet to make you pay for any diamond draw you may have? So, possibly discount AK/AA. So that leaves all small pairs, and QQ. If he had hit a set, is he really likely to check it twice - particularly with the diamond on the turn? I would discount a set for same reason as I discount AA/AK.
That means his range could be as narrow as QQ or a small pair that has not improved.
Also, you"re hand is hugely under-represented. Easy call.