Twinkle
Junior Guinea Pig
So I've had a very sad couple of days as one of my 2 boars, Ernie, sadly passed away. He had a respiratory infection a couple of months ago, appeared to fully recover with antibiotics and then the other day I came home from work to find him very sick and he died within 2 hours on our way to the vet. 
Anyway, I realise I have a duty as a responsible pig mum to find a new friend for my bereaved piggy, Bert. He is 2 years old.
I've had him checked over by the vet who says he's in perfect health and that I should feel free to get him a new friend whenever I am ready (I never will be). I would like to wait a couple of weeks just to be completely sure he is healthy first but also don't want to leave it so long that he becomes depressed. He is eating and drinking fine but does seem a little more skittish which I assume is down to him feeling alone and unprotected.
My question is, if you were in my position, what kind of friend would you ideally seek? A grown up boar, baby boar or spayed female? I understand spayed sows are quite hard to come by so I guess my realistic options are the first 2. What would you look for if you wanted to try and minimise problems with bonding etc? I know adopting a piggie in need of a new home is the right thing to do and ideally what I'd like to do but what are the chances of it working out?
If it's relevant, I am genuinely unsure which of my piggies was the dominant one. They had a very similar temprement to each other. If I had to pick, I'd say Bert is probably dominant but it's never been clear cut.
I'd really appreciate your guidance.

Anyway, I realise I have a duty as a responsible pig mum to find a new friend for my bereaved piggy, Bert. He is 2 years old.
I've had him checked over by the vet who says he's in perfect health and that I should feel free to get him a new friend whenever I am ready (I never will be). I would like to wait a couple of weeks just to be completely sure he is healthy first but also don't want to leave it so long that he becomes depressed. He is eating and drinking fine but does seem a little more skittish which I assume is down to him feeling alone and unprotected.
My question is, if you were in my position, what kind of friend would you ideally seek? A grown up boar, baby boar or spayed female? I understand spayed sows are quite hard to come by so I guess my realistic options are the first 2. What would you look for if you wanted to try and minimise problems with bonding etc? I know adopting a piggie in need of a new home is the right thing to do and ideally what I'd like to do but what are the chances of it working out?
If it's relevant, I am genuinely unsure which of my piggies was the dominant one. They had a very similar temprement to each other. If I had to pick, I'd say Bert is probably dominant but it's never been clear cut.
I'd really appreciate your guidance.