Is there a cheaper alternative that fits (4-8 GB RAM) for my laptop?

https://www.speicher.de/arbeitsspeicher-8gb-ddr4-acer-aspire-5-a515-51g-303x-ram-so-dimm-sp256012.html

Here is the link, are there others that are 100% fit and cheaper? (need 4-8 GB ddr4)

Basically, you can use any memory whose technology (DDR4), clock (2133MHz) and type (SO DIMM) are identical.

Amazon offers appropriate storage, for example, from around 35 euro. https://amzn.to/...to/2X24Ran