Would you (or any other reader without commercial bias) please
recommend an inexpensive and reliable vendor for electronics
parts for projects such as this one

Well, you could try Radio Shack, but they seem to have less and less
parts available nowadays.

For mail order, I can think of three, but they may require a minimum
order.

www.digikey.com
www.jameco.com
www.mouser.com

Also, I have a few items for sale on my
website which may be of some use.

http://ourworld.compuserve.com/homep...owden/sale.htm