As I understand it, plastic surgery is possible in cases of partial penectomy. Although it is rarely attempted in the case of radical penectomy (complete removal), I do believe that some surgeons can reconstruct the penis using skin from another part of the body such as the forearm. You would really need to speak to a professional about your options.

I don't want to contradict your surgeon since his opinion is obviously far more qualified than my own. According to the study cited above however, there are men with implants who have undergone penile augmentation (surgical length and girth enhancement) with some varying degree of satisfaction. Your surgeon may be keeping your best interests in mind since there is risk inherent to any surgical procedure and he/she may believe that the danger far outweighs any potential benefits.

You may wish to ask your surgeon if using a PDE5 inhibitor (such as Viagra) might help to improve your condition. That was also mentioned in the study as one treatment that provided patients some relief from penis size dissatisfaction issues.