Do you have a friend with a big garden where you can put up a marquee for the reception?
I think this can sometimes work out really expensive - as marquees are a lot of money to hire (thousands, usually)
I do think this is definitely do-able though! Whereabouts are you? Is there a lovely registry office near you - for instance, Colchester Town Hall is lovely - you could get some lovely pictures there and then go into town to a cafe with some outside space and get them to put on a buffet/meal for you. Lots of smaller venues won't charge a hire fee - there is a lovely coffee shop in our town with a patio and lots of seating that will give you exclusive hire from 4pm onwards for free and you buy a buffet and they can provide a cash bar (where they get their profits I would imagine). Would this work?
If you went for a SUmmer wedding, you could have a later ceremony and still have light for photos, and also have the added money saving bonus of only feeding people once - if you chose winter, you might want to be a bit careful as, say, a 4pm wedding would leave you with no time for pictures as it would be dark by the time the ceremony was done.
Or, you could go for a lovely meal somewhere with a private dining room for a small number of people - 20 people, say 30 per head for a set menu, I think you could get somewhere nice for that if you had a good look!
Otherwise, you could hire a village hall and do it all up yourself - if you look around I bet you can find a lovely rural setting with outside space etc and get the 'country' feeling you mentioned.
I really think that you can do it in 2 years - where are you so we can get searching for some of the big things for you and give you an idea of what you can get?
Also, as someone else said, a second hand dress is a GREAT way to save a bit of dough