Ill send you the invoice, which will have their bank details on it and you can pay them directly; itll take a week anyway so there isnt a hurry
With the tube, Ive had success with these guys making a hole to exactly fit a supplied tube, so that it was 'jammed' in and was never going to come out again - is this what you are after? If so, is 16mm the /exact/ size? Just so that I have not interpreted something entirely wrong, could you sketch a rough pic with the required dimensions, just so nothing is lost in translation?
Email me at scott@trout-slap.com
Is there anything else requiring cutting to do with this project?