For the sort of slope you can drive a landrover up you can probably use any skis, although normally you would want the correct length. As others have said skis may not be adjustable enough in the binding to fit any boot, if you get ones that are roughly the right length then there is a good chance the previous wearer will have had similar sized feet. The correct length will depend on the style of ski – there are usually a lot of old style straight skis going cheap on ebay. Make sure the bindings are set quite loose if you are inexperienced and especially when skiing over unknown obstacles.
Normally blades don’t come with quick release bindings. One the one hand being so much shorter the risk of rotational injury is less, but on the other a getting smacked in the back by your own blade really hurts. Standard blades aren’t good off piste – but then landrovers aren’t great in thigh deep powder either! There are some blades which are “wider” / “fatter” than others and so better. Blades are really designed for carving though – not straight line speed. There is a lot of negativity about blades, although I think at least 50% of it is just snobbery.
I have a pair of old ex hire (so easily adjusted bindings) carving skis. IIRC they are 175s. One has some damage right at the “tip” at the back which was glued back together by the local ski repair shop. Its a non load bearing area and has been fine for general mucking about on Scottish slopes.
I have a pair of wide blades which have seen very little action and whilst fun I could be persuaded to part with; as I would quite like to get some half decent skis.
If you are interested in either or both of those I will pop up the loft later and get some pictures and more accurate details.
However I think you are mental.