I tried to contact the author for clarification on where the part about getting a gun in PA came from, but I didn't see any contact information. Am I being unreasonable expecting reporters to research their facts before printing an article? At least someone called out that fictional scenario in the comments section.
That mower, with a working engine, is worth about $2,000.00. A problem/non working fixable machine can probably sell for about $750.00. More if it's a hydro. Harbor freight has 22HP vertical shaft engines for $800.00. Relegating a commercial mower to a parts machine takes more than a blown engine.
EDIT: I just looked up Scag walk behinds and they only offer the 61" in a hydro. So in it's current condition you can get close to $1,000.00 for it on CL or FB, If you slap a HF 22HP engine on it, you could sell for 3K.
The G2 trigger did cause some minor peening on the NPAP and C39V2 that I previously owned; however, the mushrooming settled down at around 500 round mark and it never impeded the functioning of either gun.
You should be able to replace the TAPCO hammer with a surplus hammer without any issues; however, I think that you'd be fine with just taking a hobby file and knocking down the burrs on the carrier tail