Great deals on those! If you can post images (or type up the text) of the stampings on that Bruyere, we can help you. They may be faint from age and use, but it doesn't take much to be able to get a general idea of the time frame.
By the way, on that Bruyere, there should be stamps on each side of the shank (the wood part that the stem plugs into). Oh, and no, a loose stem is not a problem and is very easily remedied.
Thank you. I'll upload a couple more photos of the Bruyere. The Briar has a thin metal tube that runs through the stem to the bowl, the Bruyere doest seem to have this though, is it missing?