Magna-fluxing found a Crack in one of the heads

The machinist found a crack in the cylinder head I have after magna-fluxing them.

One of the guys answering the phone says it is a crack directly connecting the two valve seats -in between them, connecting them.

Is it worth paying to pressure testing them, can they be repaired, is it worth replacing them?

Does a pressure test not incorporate the dynamic stress of heat & combustion cycles?

Would you continue to have the head pressure checked or just look for another set of heads?

Is there another 360 cylinder-head serial number that will match-up (combustion chamber/-I/E runners) with the good 4071051 head that I have in the shop?

these are stock heads going to a street 360, A833, F-body with a mild cam:

Lunati 10200301, 275/275 477/477 STREET MASTER HYDRAULIC FLATTAPPET CAMSHAFT 07401

thank you very much for your time and consideration!