Why are my models loading so slow?

[lemonbanjosupply]

https://lemonbanjosupply.github.io/

If you go down to the "headstock" tab and use the options under "Which headstock shape do you prefer?", this will activate a change in the model source.

When the website is local only, it loads fairly fast. Takes like a second to load. But when it's running on the actual internet, it takes a good 10 seconds or longer at times for the models to load. Once they're loaded they're fine, and I can switch models no problem. But when they load the first time they seem to take forever.

The link above is the website in question. What do I need to do to fix this loading issue?