I've used the 'Size Matters Pumping Kit'. They make one with smaller tubes that stimulate transmale equipment in addition to the ones for guys with bigger packages. The one for transmen is marketed more toward chicks but has a couple different size tubes to pump yourself into.
From there, stimulate it by jacking or humping something and you'll feel it right where it should be, and you can stick it in a fleshlight or other stroker.
Less spontaneous cuz you've gotta pump but hey it's worth it when you feel motivated!