I’m sorry for your loss.
Please only get one boar. Three together will not work - it’s a huge recipe for disaster, even if you can provide the space three would need (a boar trio need would considerably more space than normal sizing requirements for say three sows).
If you try to put three boars together you risk fights. The aftermath of a trio attempt would result in the best case scenario that two remain a pair and you would end up with one single. At worst, all three fight, none can live together and you then need three separate cages.
As a bond comes down to compatibility, if there is a rescue centre you can get to then that is the best way to find a new friend for him. They can ensure they are a match.
If that is not possible and you have to buy a piggy from elsewhere, then you would need a plan b in case the bonding failed ie they would need to live in side by side but separate cages.
Bonding is done on neutral territory. You put the piggies together in a neutral space for several hours and see if they get on. If they do then you clean out the cage they are to live in and mark it with both their scents by rubbing soiled bedding and hay from the bonding pen inside the main cage. You then move them to it. It will then take two weeks for them to fully bond.
Make sure you use only two door hides in cage (no hides to be used in the bonding pen) and that the cage is big enough (180x60cm recommended for two boys).
The guide below explains further
1 Introduction
2 Pre-bonding
- Quarantine and sexing
- The need for a plan B
- The rule-breaker: Youngsters under 4 months (sub-teenage)
3 Setting up an introduction
- Getting to know each other
- ‘Buddy baths’ – why not
- Scent swapping - why not
- Setting up a neutral bonding area
- How to start the bonding
4 Acceptance phase: Do we like...
1 Singles and Pairs
Singles: Challenges and solutions for different singles situations (link)
Pairs: A closer look all possible pairings (link)
2 Trios and More by Gender
Boars
- Trios and quartets - Why better avoided
- Large Groups...