Assistance needed regarding chastity cages and dimensions

My wife and I are relatively new to the chastity lifestyle. Before investing in a custom device, I’ve picked up several inexpensive models to see what works best for me. Currently, my preference is leaning toward a Jailbird from Mature Metal, but I’m not certain which size dimensions would suit me. I’ve experimented with some smaller metal cages, yet they tend to irritate the left side because my left testicle sits higher than the right one, prompting me to look for more gap distance. To address this, I purchased a CB6000S equipped with spacers and gave it a try. However, achieving the correct spacing between the device tube and the base ring required using the largest spacer available. This pushed the tube out so far that I struggle to fit inside; my soft length is only about 1.75 inches, which makes entry difficult. Essentially, what I need is a device with both a short tube and ample gap distance. Does anyone know if there’s a CB6000SSS model or something similar with a very short shaft but adequate spacing? My goal is to stay chaste for my wife as long as she wishes, though the longest I’ve managed wearing a metal cage was three weeks before pinch wounds and rashes on my left side forced me to remove it. Any suggestions?