Automatic currency based on product type

Hi guys,
Firstly, this plugin is absolutely AMAZING!
My situation is: I need to do some customizations for a special project in our website for which I created a custom currency and a custom product type (via custom code).
I used some code found on your forums to add that custom type to the product adding page and it shows fine in the product type selection, but now I need that when the type is selected, the currency to automatically change to the custom one that is assigned to that prod. type.
Is there a hook I can use to tap into the product type selection action and what hook to use to change the currency?
I suspect for the currency change it would be a JS snippet maybe?
Looking forward to any advice.
Thank you very much!

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