Hi Moth, In the past when I have investigated laser cutting the response has always been that a minimum £80 or so charge will apply. Did you manage to find someone who would cut a small quantity at a reasonable price?
In the US, I use an internet-based company called sendcutsend.com. Their prices are very reasonable and service is quick. I don't know whether they will send internationally. You interactively load a file (DXF, CDR, etc.) and and choose the material and instantaneously you get a cost.
By vintage parts I assume you mean vintagecarparts. However they only do non-flexible brackets for the Altette and nothing for the New Alto. I think water jet is even more expensive than laser. I can make the foot with a plasma cutter but a little more problematic to cut the spring steel plates for the flexible mounting and get a neat job without quite a bit of grinding. Also plasma will give an HAZ to spring steel that really ought to be tempered or it will probably end up cracking.
Thanks Gary. I'm pretty sure the bracket Moss have is for Wind Tone horns. The spacing of the bracket mounting holes is the same as for 701355 but the spacing of the horn mounting holes is different. Thanks anyway for the suggestion. Gus.