It sort of depends on what you would be doing with it.
I run Rhapsody 5.1 on my ThinkPad which has a Pentium at 133 MHz (and 80 MB of RAM)... which is about half as fast as a 604 at 132 MHz. But I also don't use the ThinkPad for heavy graphics tasks. It is mainly for viewing HTML, RTF/RTFD and PDF documentation these days, and it doesn't have to worry about running Blue Box.
On the other hand, when I started doing a lot of web and page layout work, having a faster processor (and more memory) made a big difference. With some of my bigger projects in Rhapsody it is nice to have my 8600/300. Still, I was able to do very nice work on my 7500 (which at one point had a 604e/225, 256k of L2 and 512 MB of RAM).
Memory wise, you are most likely in pretty good shape. Processor wise, you could replace the 604/132 with a 604e/200 for about $15-20. That would put you in a good position to get a feel for the system and what different apps can do.
... there is a copy of Rhapsody 5.6 on ebay right now (
here), but it is starting at $79.
On the plus side, it is a complete set of media (rather than being sold as individual disks)... on the downside, the seller knows what it is he is selling (which is most likely why the price is starting out at $79).