I came across a tutorial that deals with Spark Fun products called Stormtrooper Voice Changer. I was looking through the part listing and realized that the SparkFun Power Cell - LiPo Charger/Booster part number PRT-10255 has been retired.
Since this is one of the crucial parts in making the system, is there a replacement part that works with the other components in the tutorial or am I just out of luck?
Here’s a link to the tutorial on the main website.
Any ‘boost’ charging board with a Lipo connector should work fine; we’ll likely have some more stock soon too 
I see. Ok, now, I have some components like transistors and cables, but I have a Nano FT232 development board in contrast to the one in the tutorial. Are the two parts relatively the same or do I need to invest in the Teensy 3.2 part?
The Teensy and Prop Shield are the critical components in this project. You’re going to need both to proceed.
Looks like I will have to wait for the parts to show up. Thanks for the response.