Thanks for your questions, Alexander! You can see a photo of the arm graft dimensions on this page, under Radial Artery Urethroplasty:
https://www.andrology.co.uk/phalloplasty...eo-urethra
There's a photo of an Abdominal Phalloplasty on this page:
https://www.phallo.net/procedures/abdomi...plasty.htm
That was done by the London team but it's not clear if that patient had Radial Artery Urethroplasty. If you have an account at TransBucket.com, you can find one photo of a completed Ab Phallo, search under Dr. Nim Christopher, and another when you search for Dr. David Ralph.
After the forearm, ALT (thigh) is the most commonly used donor site but patients need to have low sub-cutaneous fat in the thigh to be good candidates.