Well you could certainly try, many of the used class A rigs we saw from private sellers had a toad option, we have our own preferred toad and were not interested which did not come as a surprise to most sellers, all had no problem selling rig independently.
As for throwing in tools and/or other RV related items, again commonplace for most of the used class A rigs we viewed, we've been RVing for decades and already had 90% of the stuff. For the savvy, nothing trumps condition of chassis, powertrain, and roof when shopping for used class A rigs.
Although there are undoubtedly buyers out there that might be starting out with a used class A, the vast majority of those looking to purchase in that category have at least some experience in the lifestyle, throwing in RV related goodies may not impress them much.
Good luck, hope you find someone to purchase both rig and toad, anything is possible, particularly if properly priced for current market conditions. Whether it is wise to hold out for a buyer willing to acquire both only time will time will tell, let us know how it transpires.