What to do after one of my two Aussies dies

Question
A little over a month ago I had to put one of my 2 Aussies to sleep. He was almost thirteen years old. Him and my remaining Aussie were together for all that time. Our departed Aussie is deeply missed by me and my remaining Aussie.
Do I proceed to look for another Aussie now, perhaps rescue an older Aussie, do I look for a puppy?
This was the first time that I had two dogs, so this is all new to me.
My remaining Aussie is in pretty good health other than arthritis.
My heart wants another Aussie now but my mind is telling me it's best not to bring another companion in to the house for my remaining dog.

Answer
After a few weeks, if your dog bounces back and seems none the worse for wear, you might want to consider whether he/she actually cares about a companion or would simply prefer your company.  If your remaining dog is well socialized to other dogs, however, and not just the one that died, then it might be nice to get a companion for your dog, so long as it's a compatible one.  However, whether you rescue a dog, or get a pup, it is your resident dog that should have the final say, so please do have a trainer help you to determine whether your current dog likes other dogs, whether your dog would prefer males to females, or pups to older dogs.  Most rescues and shelters will provide space for a "meet and greet" (and dogs should always meet on neutral territory, not at either dog's home) and paying a trainer to go with you is often a good investment:-)  I'm very sorry for your loss.  It's hard to lose a good Aussie friend, whether you are human or dog.