Hey there!
Do you want this to be a realistic looking portrait, done in pencil, black and white? My process would be to do this by hand then digitize it, I would first provide you with some rough sketches for you to approve of then commence in on the detailing - If you initiate the chat I can send you some *watermarked* samples not available in my profile
Anyway, I could start working on this right now, just let me know!
Cheers!
Don't forget to check out my profile for examples of my work and my feedback
https://www.freelancer.com/u/certaintly.html