So there's not really anything special about an internal/G-Spot vibrator in terms of vibration strength, focus, or rumbliness. In your case, the internal vibrator component was just a better match for your clit in those three areas than the actual clit vibrator was.
So my suggestion, if you can't find the original item, is to find a modern clitoral vibrator that you think might best match your needs. you already know you want "rumbly", so you just need to find one that has the right intensity (sounds pretty strong) and focus/broadness. For instance, my wife find the clit suckers as too focused (and can't O at all from it), while she finds the Magic Wand as too broad (can O from it, but she's left numb with kind of a beat-up sensation the next day).
Quite a few bullet and bullet-like clitoral vibes should fit the bill for that. If price weren't an issue, I'd suggest the We-Vibe
Touch X or
Tango X, but both of those are premium vibrators commanding a premium price. If you need to shop around more generally, just pull up
Married Dance's vibrator page with your husband and look through all the options. Doing that can actually be a form of foreplay!
My wife is similar to you. The clit suckers don't work for her, and she's never O'd without a vibe. But we get a pretty much 100% O rate thanks to the Touch/Touch X mentioned above. It, the Tango, and many similar vibes have worked quite well for a lot of women out there. High-quality clitoral vibes do seem to be cheaper than high-quality G-Spot vibes, so looking at the clit ones might be a good starting point.