Looking for advice or recommendations (updated)

Ok so I want to pick everyone's brain here. I mainly build 1/700 scale mainly because of the small footprint they take up. I've been trying to get a lot of accessory kits mainly aircraft and weapons lately to have on hand for any dios or for when I buy a ship from Shapeways. Some of the kits that I have gotten and have been searching for are Pit-Road Skywave kits, and some other brands. One thing I have been noticing is a lot of the Pit-Road kits are no longer in production so that means the webites that have kits available have a limit per household or they seller on ebay is asking for an absorbent amount. I want to be able to build the kits and not collect them, I have been thinking about finding a way to make a mold of the kit so I can cast them in resin for when I need more, I'm not trying to copy the kits for resale or anything like that. I was hop for some advice and or recommendations, what would some of you do if you had this issue. I have found some websites from Japan and have ordered from them, and I am trying to build up a bit of a stash before my wife and I move to the UK next year, and I'm not really sure how taxes and importing from Asia will be like especially with Brexit happening. Would love to hear what you would recommend. 

Thank You