OK, there are a few things going on here:
1. A regular tire pump won't work to fill the air chamber in your fork. This is because the chamber is tiny and much higher pressure than a tire and thus you need a proper suspension pump. This is almost certainly why you lost all the air pressure and the fork now can't support your weight.
2. When you say "a froth of oil sprayed out the bottom of the fork", exactly which part did it spray out? Is your fork Solo Air (one + air valve at the top of the lefthand leg) or Dual Air ( a + valve at the top and a - valve at the bottom of the leg near the wheel axle)? Which valve were you trying to inflate? Or did you have the bike upsidedown, and oil sprayed out of the main seals where the fork slides into itself?
3. After 12 years and presumably little or no maintenance, your fork likely needs a lot more work than just seals replaced, and if you ride a lot may be beyond economic repair. To put this in context, RockShox recommends main seal replacement every 40 hours riding and a full rebuild every 100 hours - this is, as you'd expect, pretty conservative but you really do need to rebuild every 1-2 years in order to keep your fork from eating itself.
Also bear in mind that the SID is RockShox's highest end, lightest weight racing fork. It's not designed to be mega durable, it's designed to be as light and fast as possible for the type of rider who replaces their equipment every season or two. Frankly, to get 12 years out of one is a pretty sweet run!
If you're mainly commuting, and the touring you aspire to do is mainly on roads, then even a budget $200-300 fork is actually going to be better suited to your riding than the one you have, albeit a little heavier. You could also consider a rigid fork which would be under $200 and have zero maintenance costs. If the rest of your bike is in mechanically good shape then there's not much reason to change it - it's a good bike, and the handlebar and BB issues sound pretty minor.