I feel your pain!

Been there and done that... with my '95 Tacoma. It's unfortunately, a rather
poor design in the pre-'05 Tacomas IMHO!

Lucky for me, only my driver's side middle leaf broke. When I checked into replacing the leaf on that side alone, I was told that...
BOTH SIDES NEED TO BE REPLACED AS A PAIR! Not having the flowing $$$ to afford a "new" set of these from the dealership, I began a
quest for a set of used ones, from a junkyard. In the meantime... I used hose clamps to "try" and keep the broken leaf in place, which just didn't seem to last for very long, as the hose clamps would work up the leaf far enough, to allow one of the broken halfs of the middle leaf, to jump out of place.

After that section began to "hit" the gas tank... I decided it was time to get off my a$$ and find some replacements... ASAP!
As it turns out, the used ones are at a PREMIUM!!

, as it seems these leafs are notorious for breaking and EVERYBODY is looking a set of used ones! The junkyards
know this and can easily get whatever they're asking for a set!

After realizing that this was a common problem on the Tacoma... AND... just how hard it was going to be, to find a "used" set of these things, I realized I had to look outside the Toyota playing field.
That said.. I would
HIGHLY recommend that you NOT replace your leaf springs with another set of "Toyota" leaf springs... ESPECAILLY... if you plan on keeping you truck for a while.
GO WITH SOMETHING AFTERMARKET!!!!
I got mine from
JC WHITNEY 
Total price plus shipping... around $200!

btw: Nearly EVERY junkyard I
was able to find a "used" set of Toyota Tacoma springs at... wanted AT LEAST $200 OR MORE!!!
One last thing... and it is
IMPERATIVE that you do this.
REPLACE THE LEAF SPRINGS AS A PAIR!!! It's the ONLY way to insure the truck will drive properly!

I honestly can't say whether a single leaf "can" be replaced in the "pack" or not. But considering how "cheap" the leaf springs are to begin with... I wouldn't won't to replace just one leaf and then have one of the "older" leafs break too!

That could literally
nickel-n-dime you to death, in the long run! Matter of fact, unless you plan on doing this yourself... it "could" still be expensive in having a shop go through the process of disassembling the leaf pack and replace one leaf... IF... that's even possible.
One more thing... considering the age of your Tacoma, you're VERY likely to run into seized shackel bolts, like I did. No easy way to say this... but... this is just a REAL PAIN!!!

I literally had to "burn-out" the rubber shackel bushings, with a torch, just to get the shackels free! There's a steel "sleeve" inside the rubber bushings, which is what seizes to the bolts themselves. Mine were seized so bad, that once we had the rubber burned off... we had to heat the steel sleeve until it was
cherry red! And even then, we still had to slowly
work that steel sleeve off the bolt!!! Even though this was a MAJOR PITA, it was still cheaper than having to buy new shackels!

The new leafs come with bushings already pressed into them so, there's no need to have to deal with that part of the job, once you get the shackels free!

I would also...
HIGHLY recommend that you get yourself a small tube of ANTI-SEIZE GREASE and coat those shackel bolts REAL WELL before reinstall them!

My adivce... I would to replace the
entire leaf for both sides, as opposed to just one leaf. If you want to add lift... I'm sure that's possible too, but if you don't... get the ones like I got, with OEM specs, depending on whether your Tacoma has the 3 or 4 leaf pack.
Hope this helps...