You being in the UK should not have a lot of trouble finding wooden planes. I'm in the US and have been lucky enough to find Mathieson wooden bench planes that have worked well for me, but there are probably many other makers to be found there. This is an English made jack plane, ca. 1940, 17" long, 2 1/4" double iron, cambered. Try to find one that is not too badly worn.
If you are going to dress rough lumber, as mentioned above, the difference in effort between a wooden jack and a metal jack is noticeable. It'll make you reach for the wooden one.