Hi Ash Field Farm - I have re read your post, and understand that you haven't got your pigs yet. That being the case, if you are worried about boar taint, ( there is a whole thread on this subject by the way), then go for castrated males and/or females.
Depending on your breed selection, the outdoor rare breeds are slow growers anyway, and whoever advised you about females going to fat is totally wrong. We have males and females growing on for meat, and they will only go to fat if over fed. In the time we have had pigs, and we have a lot of them, I have never seen a gilt change in anyway because she wants to farrow. Unless someone can correct me, I have never heard of a broody pig. So, that is something you do not have to worry about.
With the numbers you are talking about - 10 pigs - it is also not necessary to slaughter them at 7 - 8 months. That would be your personal choice. You can grow them on to 18 months and still have beautiful meat and of course excellent sized joints. Unless you have a particular plan in mind, why not stagger the 'finishing' and test the theory yourself. Do two at a time taking the last two right through to 18 month plus.
Please make sure you do not leave one on its own though, it would be desparately unhappy and very cruel to do so.
Ree is right with dimentions and advice - his pigs were very happy in their home with plenty of room to root around, and he is now resting the land for the next pair.
With 10 pigs and land available, this may dictate how long you can keep yours, but if you can move them around and rest areas, then take the experience all the way, and please keep us posted on how it all goes, and what choice of pig you decide on.
Kate