trya [1] filed a request to merge mamepgui-svn [2] into mamepgui-git [3]: SVN repo doesn't exist anymore, yet it has been cloned on github. mamepgui-git replaces this package.
[1] https://aur.archlinux.org/account/trya/ [2] https://aur.archlinux.org/pkgbase/mamepgui-svn/ [3] https://aur.archlinux.org/pkgbase/mamepgui-git/