I’m sorry for your loss.
You are doing the right thing by getting her a new friend. At only 4 years old she could have up to another 4 years of life which is too long for her to be alone.
The best way to get her a new friend is with the help of a rescue centre. They will ensure she is character compatible with her new friend and that they have a successful bond.
You can of course decide that she is not able to edit for a rescue bonding service and instead decide to get a baby from a shop, for example.
If you do this then ensure you check the sex of the new piggy yourself.
You do need to be aware that while babies are often accepted by an older piggy, there is no guarantee as you are not able to character match them before purchase.
Bonding is a specific process whereby you put the two piggies in neutral territory for many hours/all day and see if they get on. If they do then after a day in a bonding pen, you then thoroughly clean out the hutch and then move them to the hutch together.
I will add a bonding guide below which explains the whole process.
Bonding and Interaction: Illustrated Bonding Dynamics and Behaviours
One issue that does exist in getting a baby is that a baby piggy is likely to have only been used to indoor conditions so going outside at this time of year is going to be a challenge for any piggy, but particularly a baby, to adjust to.
You would have to ensure that the hutch is kept warm and protected enough.
It would be a good idea for you to search online for sheds within your budget or speak to any local companies who may sell them.
Mine do live in a shed but it was purpose built with stables doors and internal mesh doors were also added so I can leave external doors open and still keep them protected.
