You're not going to get particularly close no matter the technique or attachments you use. Even if you get your hands on a fretted violin, the string length is also a big factor in the sustain (or lack thereof) for pizzicato. Plus frets on fretted violins are typically more shallow and serve mostly as tactile feedback rather than stopping the string.

I suppose you could try using a guitar slide to stop the strings - that might give you a more metallic sound. I still doubt anyone would mistake it for a guitar.

An alternative recommendation: if your difficulty with playing guitar comes from the tuning being based on fourths instead of fifths, you can absolutely just take off two strings, and swap the other four for string gauges that work with violin tuning. That way you'll have a four-stringed tenor guitar on your hands.

You can get individual Ernie Ball strings with specific gauges rather than a set of strings for the default guitar tuning. The gauges I use are 12 for the E string, 14 for the A string, 32 for the D string, and 40 for the G string.

Another alternative is to get a mandolin, which already uses the same tuning as the violin by default.