How short of a ski is too short?

TL;DR: Charts say 163cm skate skis are best for me, but I want a cheap 151cm pair on Facebook Marketplace. Are they too short?

Hi everyone, I am a beginner/intermediate skier looking for advice on ski length for skate skiing. I know there are charts, but I am also aware that they do not have to be followed exactly.

I'll provide some context. I first tried cross-country, fell in love with it, and wanted to try skate skiing. So, I went searching for a pair. Being a cheapskate, I took to Facebook Marketplace and found an amazing deal. It was a whole set of Madshus boots, poles, skis and bag for $150. She even threw in a pair of wool socks for me. However, the skis were 180cm... and according to most charts, my best fit is 163cm. I made it work for a couple of seasons, but I am starting to become annoyed with them overlapping.

So, (still being a cheapskate) I found a pair on Facebook Marketplace for $100, not bad, but they are 151cm. I honestly don't think I'll find anything closer to my length, as every other (cheap) pair I've seen over the past 2 years has been either less than 151cm or 178cm+.

So, what should I do? Get them, or keep waiting for a longer pair to be listed for sale?