I don’t know what you expect to pay for scrapyard seats these days. Long time since I bought any. However brand new set of deluxe Series seats are only about £100.
I fitted Mk 3 Fiesta seats in mine because I wanted to be comfortable, they were ok but a bit 'high' meaning less room between seat and steering wheel. They also felt a bit damp in the winter being cloth covered. I took them out when they started falling to bits and fitted Britpart standard seats instead. They are just as comfortable as the Ford ones, easier to get into, more durable and untroubled by the dampness problem, also I can take them out to get at the covers underneath without resort to spanners. I wouldn't go back to non-standard seats.