trigger events for product option change

-- HikaShop version -- : 2.6.4
-- Joomla version -- : 3.6.2
-- PHP version -- : 5.4.45
-- Browser(s) name and version -- : chrome 52.0.2743.116 m

Hi,
im developing a plugin that will recalculate product price in the front end based on a certain percentage taken from product option change,
(since product option doesn't have an option to use %)

example:

product name:
"custom business card print"

product variations:
1. amount (100,200,300....)
2. lamination (yes, no)

product options:
1.paper type:
a. normal (price $0) ( total price + 0%)
b. special (price $0) ( total price + 20%)
c. recycled (price $0) ( total price + 35%
d. metal (price $0) ( total price + 70%

challenge:

recalculate total product price on product option change event .

looking for the event trigger that happens after product option change. does this exist ?
if not, what should i do :
1. to catch such an event
2. what function can i use to get current total price, change it and update it on the product page (just like it happens when variations or product options are changed)

Thanks

Thanks very much.