I can't tell you here to the UK but from the UK to Brooklyn
(pretty much as close as you can get across the pond) see
below.
A Bowman twin was $34, an SEL twin $25, and a nice Marklin
mashup $18. Keep in mind these are all small engines and
lighter than yours so your shipping has to be at least the higher
number..I think?
Hope this helps you ballpark it,
Wayne