What to do when you can't afford the proper wedding gift for close family?

Let me start by saying that I understand weddings are a very loaded topic on reddit. Different countries, regions, and cultures have different traditions that vary wildly - that doesn't mean one is right, the other is wrong, and everything inbetween is tacky. I am not here to judge any of that or budget shame - this is purely about what to do in my current situation regardless of monetary value of the gift.

WITH THAT BEING SAID...

My cousin is getting married next week. Boyfriend and I live in a different state from all of my family and will be traveling home for the wedding. We are choosing to stay in a hotel because my parents house is kind of crowded, so we already spent money on that and will be on travel. As of 2 months ago we became a 1 income household - my boyfriend is not working (although trying to) and we are getting by on my income. We aren't in dire straits and drowning, but the extra expense of a monetary wedding gift that is within the accepted means of my region is way out of our means.

I have already spent money on gifts for the engagement party, bridal shower (and travel), and now travel and hotel for the wedding. Where I am from, the wedding gift is always cash and you calculate how much using the "pay your way" idea so it would be about $250 for me and my boyfriend. Again, I understand most places don't do this and many people have strong opinions on that way - but this is how it's done where I am from and what everyone does.

We can not afford $250. Not even close. Maybe $50, $75tops. I thought about maybe buying another gift from their registry but all that's left is a $50 trash can. Seems odd to give as a "happy long marriage, well wishes!" gift and also wtf a $50 trash can? I feel really stuck. Our families don't know he's not working and we want to keep it that way, but we can't show up empty handed. What the hell do you do when you can't afford the wedding gift?