There are actually several generations of these, made on contract for Bluegrass under the Winchester name. The first ones were the nicest - bone, stag, celluloid, pearl, all made by Queen Cutlery. These were made circa 1987 -1997. All with mirror polished carbon blades.
Then Queen made a less expensive "Workman" series of traditional slipjoints, delrin imitation black bone handles, brush finish stainless blades.
Utica has made some also, originally in the "tactical" styles, multitools, and some brass handled slipjoints. Now Utica is producing some traditional slipjoints, delrin handles, quality not quite up to Queen, but less $.
As was mentioned, now some are made in China - I have seen these at Mall Wart.