Hi do any of your friends/family garden and you could share some of their seeds.
If you look at Wilco's, B+Q,Focus or garden centre they do their own range of seeds and are smaller quanties in the packet.
Saying that seeds have a best before date on the back of the packet so if you buy some in the spring some will have two years on them and if you seal them up with selotape after sowing keep in a tin box with a lid so you dont loose them dry and cool will keep quite happy.
have fun Teresa