Recommendation for SRAM Shift Lever service

Dear all, I have an SRAM Rival 22 right hand shift lever that's appears to be failing (to do anything it's meant to). Normally I'd either service it myself or replace it but it's a) possibly beyond my understanding and b) very expensive (€300) to replace. Given that, can anyone point me in the direction of a Dublin-based mechanic they'd trust to work on something like this. (There are a couple of shops in my area but past experience suggests their competence is fine for basic adjustments but not so much for finer details like the internal intricacies of a combined shift/hydraulic brake lever.)