The Ortofon LH-9000 would seem to me to be a bizarre recommendation in this case.
Cartridge/Tonearm resonance is just about ideal with the OP's combination currently and if Pintree's experience is to be believed (and I see no reason why it shouldn't), it doesn't really make sense to replace a 7 gram headshell with one that weighs almost 17 grams.
I really like the Yamamoto HS4 for the money, but even it comes in just
under 11 grams so I would not be inclined to recommend it in this case.
If I was the OP, I'd be looking at headshells that weigh in the 7-9
gram range. Yamamoto Boxwood is cheap and might be worth a try at around 8 grams (no experience with it and it may be horrible!). But I certainly wouldn't be spending a lot of money on any headshell weighing much more than that (at least not before auditioning, which is clearly difficult to do with headshells!) if I was the OP and committed to that cartridge/tonearm combination.