Sources tell TMZ ... the photos were taken at a hotel party ... a short time before The Flying Tomato won a gold medal at the 2009 Winter X-Games for Superpipe (haha ... superpipe).

We're told several party goers managed to snap photos of the naked romp -- but we're told people close to White immediately tried to run damage control and told people to erase all of the pictures.

Now, at least two of the pics have surfaced ... one featuring Shaun making out with a hot blonde chick in front of other people ... with their clothes on.

The other pic shows Shaun with the same woman -- sans clothes -- in the middle of a missionary-style embrace on a bed ... with Shaun grinning at the direction of the camera.

TMZ has seen the pics ... let's just say the ginger carpet matches the ginger drapes.

We're told the buyer is looking for a serious payday -- but so far, has not found a buyer.