Hi all. I've posted this on another gunsite but would like to get some other opinions if possible. Ive been looking at an antique double rifle online and am rather confused as to who is the actual maker. The side locks are engraved with J. Beattie, the action is stamped on the flats with P. Phillip & Son and the barrels are marked on the rib E. Harrison & Co. 226 Strand. Its in .500 bpe. Now some research Ive done says that Beattie was a seller of others guns as well as a maker himself. Could this specimen be built by one of the other two makers named on it and Beattie was the seller, or did some makers farm out some of the work and put the components together and put their name on it? The only possible concern I have is that this gun was put together by someone using spare parts, which would be a big concern to me. It does appear to be in very good condition. Thanks in advance and Im looking forward to hearing your responses.