With some research
and some trial and error you will be able to find alternative materials from cheaper sources that work just as well. It'll take some research
& experimentation though.
I've used the fabric store nylon materials as peel ply and some landscaping plastic mesh as flow media. I've also used shade cloth as flow media which produced the best results so far (other than purpose designed flow media). The one thing I haven't really found a good alternative for is the bagging material. I've tried poly films that are available in the hardware
stores, plastic shower
curtains, garbage bags (not bad for small parts) etc. None of which I'd feel comfortable using on a large part involving $1000's of other expensive materials.
Other consumables such as bag sealing tapes (butyl rubber) can be had cheaply from RV supply stores, they use it to seal windows. I've gotten it as cheaply as $2.50/roll for a case of 24. I use all hardware
supply plastic pipe and T's from Lowes for the resin feed and vacuum lines. I built my own resin traps from hardware ABS pipe & fittings. My pump (Robinair 15500) came off of e-Bay for $200.
The process by itself produces a lot of waste material. That's probably one of it's biggest drawbacks for the hobbyist. Unless you can buy in large volumes (economy of scale) you'll pay a premium for these materials. If I was building a whole boat
say worth $50K then $200 for a roll of Stretchelon isn't so bad. If you're near a boat building company that uses this stuff you might ask if they can get you a deal or sell you some roll ends etc.
There have been some innovations in the materials used such as core matting that's also a flow media that stays incorporated in your layup
. I think it's called Enkafusion.
The white tube on the right is the resin trap. it has a clean out plug
on the bottom. The black tube is a vacuum reservoir I plumbed into the system ' cause I had it. You can see the Robinair on the left.
I don't like to leave electrical equipment
running unattended so I added a vacuum control setup to run the pump when needed.
Details on how that works can be found on the joewoodworker.com website. I think I put the whole thing together for less than $350.