Minimony?

What time are you planning? You can get away with just a few apps and cake at a non-meal time, but you need to feed people the equivalent of a full meal if it is a meal time. You can check out local restaurants in your area for drop off catering. A reception is just any gathering after the ceremony, and it is to thank your guests for coming to the ceremony. You don't need all the dances or anything for it to be a reception.

Nice idea, smaller gathering, and bigger party housewarming style in a few months, rather than a reception. 🙂 But can the taco truck. It will be a shorter post ceremony gathering, and I think it would be important that you have a short, not multicourse meal seated, not the disruption of different people from a truck served together, not people who want to sit and talk sit together.
With apps people usually go for many, with cocktails. But as a meal, you want a few where 2 make most of a meal, one Vegetarian (with cheese or egg, cheese has no animal stuff added, so kosher or vegan cheese.) Something Italian, like Manicotti, with a separately cooked meat like sausage.
And meat kebabs, with separate kebabs of grilled vegetables, and easy rice pilaf. Kebabs of vegetables could be made for all eating italian choice too. Start with baskets of rolls for server to put on a plate right arte food. With 40 people, 3 servers should have everone within 10 minutes. And people are seated and talking, while others are being seated, and being served. A buffet of passed apps or a truck will be too unsettled. A buffet or passed apps take longer and more staff with such a small number eating.

Agree with Hannah- depends on what time your wedding is. Check out Yelp for restaurants in your area.

Seriously! I'm so excited about these pop up weddings I feel like I have to tell everyone! I'm I louisville and when I messaged venues on WW about my small wedding of 10 guests I actually got a few replies about what they call "pop up weddings"!
We just booked our pop up. It's 2 hours with an outdoor ceremony, indoor reception. They decorate, provide the officiant, the cake, the decor and any add on you want! It started at $895! We went with an outdoor ceremony add on so that brought us to $1200 but that's still a huge steal for an entire wedding! Look into that. It's amazing!

Get drop off catering from your favorite local restaurant.

How many are you anticipating at your elopement?

We did a Covid elopement with fewer than 10 guests, standing only, and cut and served a small cake and had individual mini champagne bottles for guests. The entire event was us doing our vows, exchanging rings, sharing a kiss, doing a first dance, signing our wedding papers, and having cake and champagne, and it lasted maybe 45 minutes tops.