I use two machine shops. If you’re wanting quality machining I’d recommended L&M Engines in Hatboro, PA. They seem like an overall good shop.
https://lmengines.com/
I also use ECAM in Glenside because he’s closer to me. He’s a nice guy and has done me some favours, though honestly his machining on my cylinder head was not very good and I had to take it to L&M. But he knows engines and does other things well (for instance he resurfaced by DMF with no issues, or getting the ridiculous phaser bolt out of my Audi’s exhaust cam, etc.).