The sourcing part is where you’ll struggle I think. As they will almost certainly be second hand. So someone bidding via eBay or contacting breakers on your behalf. I really don’t think you’ll get anyone to do that for you. Way too much hassle, for all sorts of reasons.
If you scour eBay & buy the seats yourself, you’ll need universal adaptor plates to go with from say, THQ. At that point it’s fairly straightforward to do that bit yourself also. But if you’re really not keen, getting someone to fit only, shouldn’t be an issue at all.