Withnail that 300v is an excellent camera but it'll go for over a tonne no sweat (if not snap it up mate).
Go for a 300 theres shed loads of features once you get used to the camera and lots of cheapish accecories too such as lenses (if you dont just buy canon and try sigma for instance). Plus they are not much to buy i paid £60 for mine with lense, filters, carry bag and batteries and a film.
Processing aint that expensive i paid four quid odd for 1 hour processing at asda and its only a couple of quid for next day or 2 day processing. Films can be bought for a quid or so if you go to local superdrugs or savers etc or t'internet.
Its a laff not knowing if that shot you took ages setting up came out exactly as you hoped or not :-? . Once your used to it though its second nature then if your hooked upgrade to a more expensive digital version. At least if not youve only lost £60 as opposed to the £400 + for a digital slr.