Reddit reviews Adafruit Accessories Quad Level-Shifter (1 piece)

You can get those level shifters with Tx Rx labeling. It's the same thing, just different board labeling.

But those level shifters are relatively slow, which might be why your 3.3V to 5V pulse is getting lost. Try an active buffer like the 74HCT125 buffer to shift 3.3V to 5V at high speed.

I linked the one I'm using. I also just ordered some of these and these. Will those both work?

Also, are there any smaller options without the pins sticking out? I just want a small little one channel converter...