Up for sale here is this recap kit for a pair of Optimus 1B speakers, #40-2005. This will let you completely recap two (2) Optimus 1B speakers. This kit is not for the regular Optimus 1 speakers;, that kit is here.
These are brand new Supertech MPT (metallized polypropylene film) capacitors, which are super-high-quality and will sound nice and clear. There are two 15 uf caps, one for each speaker. The old caps are pretty bad by this point, but these new film caps will get your speakers singing again!
Some Optimus 1B speakers may use 4 uf capacitors instead of 15 uf. If that's the case, you should buy those, not the 15 uf. Please check before you order.
These are fairly easy to install as long as you know what you're doing. You will need a decent soldering iron, solder, a Philips screwdriver, wire cutters, and a hot glue gun or rubber cement to aid in mounting the caps.
These are much higher-quality than the original caps, and are also much larger, just FYI. They will mount just fine.