Just how involved would depend on what model of snowblower you have. DLE is a marketing designation. Your model number is on the back of the base. I think you have a “newer” DLE which could have the stand up chute control support post. If that’s the case and you don’t have the older type which has the cross support rod bolted to the head then you can mount a Honda or clone OHV.
Not having a winter engine is not a big deal depending on where you live. In Mass it does not matter. The Honda snow engine does not route exhaust to the heater box like Tecumseh L-heads. It has the muffler separate but does have some cover plates which may be to keep snow out or possibly keep in some block heat but again it would not matter in most places. The winter engine air filter footprint seems to be the same as their regular GX engines but does not have a filter inside.
The bolt pattern for a bigger Honda or clone will be different than on your 8 but your chassis is probably pre-drilled for bigger motors as are most Ariens machines. You can check at the Ariens site for base part numbers on bigger machines which will probably match your 8. An 11-13hp GX clone will bolt right on to most Ariens chassis.
The next thing would be the height of the crank which will be a bit higher and can be dealt with by an increase in belt size.
Sticking on a bigger GX or 11-13hp OHV clone is not so difficult but you’d have some leg work to do. Overall as Snowman said putting on a stock 10hp L-head would be simple and is a decent setup up from an 8.