This might be kind of naive, but you could probably get a close approximation by counting how many inputs there are and multiplying it by the avg size of a signature.

I don't know enough about txs to say how accurate this would be.

You might think it is implicit that a person who helps you find X would receive a tip. But perhaps if you were to explicitly state that, you might find someone to respond with that specific information.

Here is a link to the structure of a block: https://www.oreilly.com/library/view/mastering-bitcoin/9781491902639/ch07.html#:~:text=Structure%20of%20a%20Block&text=The%20block%20is%20made%20of,contains%20more%20than%20500%20transactions.

So there you can calculate the space that can be taken up by transaction. It gets difficult because not all blocks have only transactions in the payload.

Then you have to multiply with the byte sizes inside each transaction:https://www.oreilly.com/library/view/mastering-bitcoin/9781491902639/ch05.html

Unfortunately this can also vary...