What a fabulous piece of glass that is, I love that kind of thing. I'd really like to see the other pieces you refer to.
I can't find anything under the name Makas - but I don't have a lot of information on engraved glass, to be honest.
I see that you're in Holland, and this probably isn't much good to you, but this is the address of the Guild of Glass Engravers in the UK.http://www.gge.org.uk/contact.html
I remember trying to contact them about a year ago - some of the numbers were out of date then. :x If you don't get any success here, then it's maybe an avenue you could try?