Two other superb, online resources for the Great Highland Bagpipe are:
http://www.thebagpipeplace.com/
http://www.bagpipejourney.com/
The main differences in turning patterns are Plain (no combing), Flat combed (patterns of lines, but no beading) and Full Beaded and Combed (both flat combing and rounded, beaded patterns). I happen to prefer Flat combing with no beading, which is what your G&M pipes evidently had.
MacLellan does some superb, vintage looking pattern pipes with flat combing among modern makers of quality:
http://www.highland-pipemaker.com/
My Clans: Guthrie, Sinclair, Sutherland, MacRae, McCain-Maclachlan, MacGregor-Petrie, Johnstone, Hamilton, Boyd, MacDonald-Alexander, Patterson, Thompson. Welsh:Edwards, Williams, Jones. Paternal line: Brandenburg/Prussia.
Proud member: SCV/Mech Cav, MOSB.
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