However it would be possible to do via the channel_sellables endpoint https://api.veeqo.com/channel_sellables/:ID {"remote_price":46}
I found this information by performing the request in the UI with the network tab of chrome dev tools open, you should be able to mirror most requests the UI makes via the API.
PLEASE NOTE:
This is not official supported, you might experience unexpected behaviour and things might break at any point in the future.