For scar reduction, I`ve successfully used "Bio-Oil" and "E45 Cream", though not of course, concomitantly! Both are available over the counter in British Chemist`s shops, or from price-reduction shops such as 'Home Bargains'.
The Bio-Oil is typically advised for stretch marks and C-Section scar reduction, so is likely to be perfectly safely used on recently post-GRS tissue......I`ve found it to be eminently effective, both on my revision scars and the several decades-old original GRS (keloid) scars; especially, when used over a sufficient period.