The Blot Toad is what the are referring to and yes, I've seen it put on a palaquin as a joke Slann. As long as you have the proper base size, you can proxy a homebrewed model. Most LGS and some tournaments don't care.
My personnel recommendation is to play 1K first as it may better fit into your 90 minute attention span. The downside to your model list is that you won't get a true feeling for Seraphon's current meta, but you will get some feel for it with the EotG summing potential and still having one teleport available to you. Another recommendation is, if you have a bunch of models from several armies that you could see yourself doing without, try to sell them and then buy a few Seraphon models to really get a feel for the army. You wouldn't need many with your current list. I got by with 2K for a long time only having 6 Rippers and 3 Razordons and filling in the rest with heros and Skinks. My minimum recommendations would be:
Slann
Astrolith Bearer (this can be easily kit-bashed from a Start Collecting box)
2x Razordons
3x Rippers/Terradons, proxy either way
40x Skinks, giving you 60 total. Eventually, I'd shoot for a minimum of 100 Skinks, but I'm not even to that point yet.
Just some ideas if you think Seraphon would be your go to army.