Adhesive replacement for pixel 4a

If there is no pre-cut adhesive available you’ll have to resort to those tape rolls like you linked. I would suggest you to get a few different sizes because there are some places where a bigger strip might be appropriate, and other places where you’ll need the smaller sizes (on the thin edges for example). I don’t recommend to only go for a large size and trying to cut it smaller since that generally doesn’t work well.

Ifixit carries 1mm 2mm 4mm 8mm Tesa tape in their store: Tesa 61395 Tape which is a well renowned brand.

My personal collection also has 3mm and 5mm but I think you’ll do fine with a few or all of the sizes that ifixit caries. 8mm might not be suitable for mobile phone repairs though :-)

I also had a quick scan on eBay & AliExpress but none of them seem to have the pre-cut adhesive for the Pixel 4A unfortunately.