Here are 7 sketches I made today. Each one was drawn inside a copy of my Mecha Zone 1.5 book as a reward for pre-ordering the book. I think it was a pretty good day! I just got back from the post office... these went out randomly to US pre-orders. Maybe one of them is in your book?
These aren't supposed to be any particular mechs, just whatever my brain barfed out, but some of them are pretty generic so they may be reminiscent of existing mechs. I'm sure you'll let me know