You're probably best building the collection up yourself coin by coin. I did it a few months ago and it was quite an enjoyable process tbh. Every time I found one I needed got me closer to the full set
I can only speak for myself as someone who has the full set in a display case, and you'd have to pay me massive overs to part with it. Don't think people would sell full sets cheaply which is why I think you're best just building the set yourself