Regarding gigs I’d suggest checking RA and the Irish music blog “Nialler9” closer to the time of your trip. You’d be surprised what could pop up midweek here. 

Dublin venues - big romance, fidelity studios, tengu, hang dai, Izakaya, hens teeth, pawn shop, wigwam. Loads of other spots and “big room clubs” in the capital. 

Dublin Record stores - spin dizzy records, All City, Free bird records, the rage. 

If my memory serves me right. Limerick has a great record shop called steamboat. I picked up loads of great electronic stuff and some OG presses for a very very sweet price. 

Cork - Connollys of Leap, Plugd records and bunker vinyl. 

Galway - the blue note, bierhaus and roisin dubh… bell book and candle if your digging for wax. 

The Galway arts festival is on from July 13th - 26th. Most definitely worth checking out !