GoKapital advertises up to $500k personal loans on an unsecured basis, with a higher chance of success if you're partially secured (admittedly, putting $50k down instead of investing it elsewhere is an additional cost to servicing the loan, but even 6-12 months into a tech career you should've had $50k saved up, so that shouldn't be a barrier to entry at least).

Also, ordinary banks might not advertise outrageous personal loans, but when your base salary starts at $300k and has a history of increasing (i.e., you don't _need_ the money and just want it to power a particular total comp over time profile, especially when you keep at least 50% of your total comp in cash rather than leveraged investments), most mainstream banks are more than happy to furnish somebody to personally service your account and make a loan like that happen.

Separately, if you live in parts of the country (US-specific) where salaries like that are common, you probably have a down payment of $200k+ if you have a mortgage and would have little problem grabbing a partially secured loan against your current equity.