I own one of the threaded Buckmark rifle barrels (I don't know if these are advertised, they did a special run and sold them on rimfirecentral) and it is great. Accurate, much lighter weight than the stock bull barrel (which allows the little ones to handle the rifle a lot easier), thread job was perfect, easy to drop right in.
I've seen their other products at the SHOT show as well . . . everything I handled seemed well made and the people were very knowledgeable and polite. I would do business with them again if I ever needed something they sold.
If you don't get many responses here, try a search over at rimfirecentral . . . lots of folks have their products.