I say shop around, and then suit yourself, and let your father find the right one, or ones, for him.
There are many different guns out there, so go and try as many of them as you can. Then, when you decide, decide where you want to buy. Online, or from a local gun store.
New or used.
And remember, nobody likes to have just one.
You don't have to keep any gun you buy forever. If you buy this or that, and after a while don't like it, sell it. And get something else.