There are two marbles which may count as red ones.
1.) The one on the top right is coloured somewhere beteen dark red and dark brown.
2.) The base of the one in the middle of the right half is nearly colourless, but it's surface is littered with red glas crumbs. They are somehow melted into the surface. But it hasn't got a smooth surface, like normal marbles. It has a realy bumpy surface.
Your Welcome I Know Have With Spots And A Rough Surface Like Yours I Have Green Blue Maybe And A Orangish Red Coloured Marble. Red Marble Are Hard To Find So Is Pink And Purple Wish They Made More I Actually have 3 5cm Marble I Bought Them In A Packet With 1 Of Those Marbles With 54 Other Varied Sized Marbles $2 Each Not Bad So I Got 3 Packets Now There's None Left XD