Southampton is a bit far from me, I have been to Bricket wood years ago and there was mostly teams BUT individual people do attended and I doubt anyone would say no at playing pick up games with you guys. Personally as it’s a father and son thing I would suggest calling local sites explaining you want some days to train with your kids and see if they can fit you in somewhere. Not sure the cost or what the terms would be. If you have looked at videos and done research there is no reason why you and your kids can’t train privately and personally running drills repeatedly with your advice an input would be more beneficial. Once you all feel confident in the drills and the standard in which you do them. Explore busy sites with the confidence and knowledge you have put in significant work. Nevertheless I’m going to a walk on, on Sunday at campaign located in Cobham. If your looking for extra people to train with I’m open to that. Like I said I’m fresh from a 5 year break and I won’t make the error of not covering the basics, and assuming I can walk in to a team or neglect the hard work needed. Dedication and as much commitment that’s financially possible. Good luck my friend.