I had been thinking about 3D printing some mirror mounts, or even machining some out of aluminium, the most expensive part was going to be the adjustment thumb screws, and the most difficult part to machine would be the mirror ‘cap’.
I have been unable to find an alternate source for the laser head, and the cheapest I could find an suitable mirror mount was for £13.00 ($19.50) each on ebay.
In the end I decided to buy the cheap mirror mounts at $9.50 (£6.30) each
the 18mm laser head for K40 for $19.50 (£13.00)
from Lightobject, the shipping and handling was I thought somewhat excessive at $24.00 (£16.00) for such a low weight, low value shipment, although on checking the USPS website, all the USPS prices seem somewhat excessive for international shipments.
The package was shipped on 30/11/2015 and arrived on 11/12/2015, so not the fastest, but I have had slower shipments also.
The parts were well packaged in bubblewrap, however one of the mirror mounts appears to have a broken thumb screw, which does not appear to be anywhere inside the package, so was probably broken before shipment and simply not noticed.
I took it apart to release the broken piece of thread, here are all the parts.
You can see that the parts differ slightly from the picture above, including better thumb screws and lock nuts as well as the parts being annodised black.
As previously mentioned, the thumb screws are not the easiest items in the world to locate or to manufacture (without significant wastage of material).
I did consider contacting Marco at Lightobject for a replacement, but then decided I would modify the mirror mounts and use a ball bearing in place of the corner screw instead.
I dismantled a 608 skate bearing as these were most likely to have suitable sized balls inside, plus these were about the cheapest bearings I had at about £0.18 each ($0.27).
I reassembled the mount with the ball in the corner and all is well, plus I now have a spare thumb screw.
Now I just need to make an extension piece for the lens holder nozzle, order a lens and cut out some mirrors.