Before concluding you need new seals, it's possible they're just dirty. Use a seal-mate, or piece of plastic film, or even a business card, to slip up between the lower fork leg & the seal to clean any grit out which may be preventing a good seal.
If you find you still have a leak, as others have said above, it's certainly a doable afternoon job if you've got tools (or home-made equivalents), a manual, & a clean work area. I'd also recommend using a camera or sketch pad to document the disassembly & make re-assembly easier.