Without starting a crap-storm about CAP, I can attest that the welding that left CAP was also downright unsafe in some cases. I wouldn't run any of the old CAP products after I broke a weld on my tubular LCA's from them.
To the OP, is it just the engine mount on your stock frame that's broken? For what you've described as the uses of your car, it would be a heck of a lot more cost effective to just weld another engine mount on unless the K-frame is bent or damaged somewhere else. Reinforce the steering box mount while you're at it and it should be good for a very, very long time. If there's more damage, a stock K frame is still a heck of a lot more economical than any of the replacement K's out there.