We don't have a Goldfever. Are you sure you've got the right name or you're on the right site.

On the German version it was called Goldfever. I mean this one: https://static.wikia.nocookie.net/howrsewiki/images/5/5d/Goldfever_Fell.png/revision/latest?cb=20131227084256

We had Shutterfly's Splint Boots on this server, for the showjumper Shutterfly.

The only way to find them is to search for horse's named "Shutterfly" to see if they have the coat, but you don't see them up for sale much anymore. And we can't message players to ask if they want to sell.

Why can't we message players to ask if they want to sell horses? Is that forbidden here?

From the information at the top of the inbox "Using this feature for advertising purposes is prohibited."

Otherwise, players would get spammed with messages if players could freely ask whether horses were for sale.

As far as I remember, it is not allowed on any server to use Private Messages for advertising purposes

That aside, most players do not sell anything unless it is listed in the sales (some players do accept offers, but have explicitly written that on their page)

Goldfever was on the German server, as it was Ludger Beerbaum's horse.
We had Shutterfly, Meridith's horse. The item itself cannot be bought anymore, every now and then you can find a Shutterfly horse in the Sales.