Don't think so. That one sounded like a real loser. Cracks across valve seats and into cylinder walls are a bad deal usually.
I fixed one of those with Lock & Stitch new valve seat and no sleeve and that engine runs strong 5 years later. In fact the guy was so happy with it he was going on and on about how that's one of the best running Flatty he's ever had.
I fixed it because he had a bunch of money ******* in the engine and wanted to save it if he could. I fixed the crack and overhauled the engine, did some sensible porting and ran a Max 1 cam.
The engine already had Offy heads and intake with dual carbs. It's in a '51 Ford sedan.
Yes it was a little scared at first but once I did the repair it looked really good.
The Lock & Stitch company walked me through it after I sent them good pictures of the crack. They have quite a few different styles of pins so they hooked me up with those and I carefully followed their instructions to the letter.
It was their recommendation NOT to sleeve as that would have a spreading effect on the area.
I should say this crack ran from a center exhaust valve pocket, through the seat and down into the cylinder about 1/2". Yes it looked bad but the engine ran.
When I was done you could hardly tell where the repair was done.