Hello Themba.
Welcome to the LaserBoy Forum.
I think the best idea for you would be to get a good DPSS green laser with analog modulation.
You can easily burn plastic with diodes, like 808nm, 658nm, 445, and even 405. They can all be powerful enough to do the job.
But I don't think you will get the quality of beam that you need to do fine marking.
A professionally made DPSS green will have a very nice, small, round beam spot.
Plus it will be nicely made in a good protective case and have a good stable power supply.
I think a 1 Watt green should cost about $1000.
That's not cheap, but it should last for 10 thousand hours or more.
Then you need to get a pair of scanning galvonometers. These are not lenses, they are tiny moving mirrors.
Once you get that setup, you will need to be able to make signal to control both the brightness of the laser and the positions of the X and Y mirrors; synchronized together.
That is what LaserBoy can do for you!
You can take an inexpensive computer sound card and modify it a little bit to make a direct coupled laser control DAC.
Then you can make your art in the LaserBoy application, convert that art into a wave file and play the wave through the modified sound card.
That will give you the signals you need to control your laser projector.
BTW I like your avatar! Freddie Mercury is one of my favorite singers of all time!
James.