Is there a simple way to convert coloured vectors into a restricted palette ?

Hi there,

I am a long-term Corel user, but first-time poster.

Currently I am working on a series of icons, using coloured source vectors to make up some of the components. I need to convert all icons into a common colour palette (think of it as a form of tri-tone). Is there a way of forcing an entire document to convert to a simplified colour palette ? 

Reading around, I know I can find & replace colours, but there are so many of them it would be an almost endless task.

The only thing I have considered is exporting as a PNG to Photoshop, converting to Duo/Tri-Tone, and saving from there, but I would prefer to take the whole Corel document and convert natively.

Any suggestions would be most appreciated.

Thanks, Craig

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