I snagged a NIB head off ebay back in the winter for 80 bucks, the head was still in the sealed box. I figured it was just the bare head, but it came with seats, guides and studs, I was pretty happy with that find. Got a set of Kibblewhite double springs, valves, seals and Yamaha buckets and keepers for it. Charlie @ Pro-1 in AZ has it now, should be back this week. He's doing a CNC five angle valve job and porting it, not sure if he cuts the guides or not, I just assumed he would. I guess I'll see next week, I'll post some pics of the work when I get it. If they cut the guides, you would just need to replace them sooner than if left at length.