We are fortunate enough to have a local import auto sales/service dealer fairly close by that we have used for routine maintenance in the past.....they never fail to slash what the maintenance cost would be at the dealership and the battery was no different, the beat it by right at half.
Maybe you can find something similar around you.
We do have a reputable Euro service shop here, but I haven’t talked to them yet. I’m assuming they should be able to take care of me, at least for regular maintenance.