How much do you think a sports related gamemode would cost; not DarkRP.

Posted this here wondering, have never really been ragged on about pricing on Gmod store ever. But wanted to see how my idea sounded.

Usually, these types of game modes are out of passion and not really paid for that much. But I was thinking about trying to pay for a competitive hockey game mode. Don't even know if it's possible in the Source engine but just having stuff like slap shots, wrist shots, aiming shots, different third-person cameras, movement as if you were on ice skates, checking+poke checking, ability to play goalie, having different models for each team, along with goal horns and replays.

How much do you think this would drive up in cost or would it even be possible at all. Sorry if I sound like a complete and total dunce for asking these things but here are some examples of some sports game modes that are somewhat similar to my idea;

https://steamcommunity.com/sharedfiles/filedetails/?id=1301275288&searchtext=football

https://steamcommunity.com/sharedfiles/filedetails/?id=104625632&searchtext=football