For something that will have to be dismantled for cleaning, a '73 is your best option. You only need to drive one pin loose to get the bolt out, and that frees up the barrel/chamber front to rear for proper cleaning.
You should be careful if considering any used '73 or a '66 though. There was a safety upgrade made to the bolt retaining assembly that will cost a couple of hundred dollars to perform if you end up with an earlier rendition.
Instead of JUST a pin driven through the bolt and firing pin extension to hold it all together a sort-of wedge shaped piece was added to the parts group that makes it almost impossible to have that extension come free and plant itself in your face.
Forget about the '94 for BP, it's just too complicated to allow for repititious dismantling for cleaning, the same can be said for the '92 (although not QUITE so). If you end up considering the '66, you really need to look into retro-fitting a lever-closed safety mechanism. They didn't come with them, and I don't know if any of the manufacturers ever fitted one down the road.
DON'T let anyone talk you into a Chapperal branded cowboy rifle of any vintage, you have been warned.