If they lock up tight, with no wiggle, and you can't see daylight between the breech and the barrel when they are locked up, then I would say go for it. If ya have an extra one, there are plenty of guys who would gladly take them off your hands. As far as the wiggle goes, you could always shim between the forend and the spacer to take out some of that wiggle, if it really bothers you. The measurement for headspace on the barrel is MAX. .002. You can check that with a plain old auto style feeler gauge. You should not be able to pull the .002 gauge out if you lay it across the open breech and latch the barrel.
cookiemann