I had a look at Pioneer's web page without success. My suggestion is if you intend playing these LPs as a serious medium i.e. you aren't going to transfer them to CD using you computer, and intend playing them through the HT you're going to need to take karkus' advice.
I doubt the HT receiver has a phono input (which gives higher gain than a CD or AUX input on your receiver) and you will need to buy a phono amp. There are a few of these around and they aren't expensive e.g. Cambridge Audio 640P. The phono amp should have the option of inputing a moving magnet (MM) or moving coil (MC) cartridge, depending on what is on or you buy for your turntable. My suggestion is that you look on eBay or similar site for a TT - I recently bought a Thorens 125 very reasonably - 30 years old but built like a tank.
You would then plug the TT into the phono amp and plug that into your receiver's AUX input. Simple, but there is a cost involved and you might want to consider whether it's all worth it. How many LPs have you got and what condition are they in? LP records need regular maintenance and you need to make provision for that as well. Considering that HT is clearly your passion, how often do you think you will play your father's records? They're not going to give the repeated sound quality that you're used to without spending some very serious money on a TT/cartridge setup.
If you're more interested in the material on the LPs than the analogue sound why not buy the USB turntable and burn the music to CD on your computer? I can hear the shrieks of protest now from the analogue fans, but this might be a practical solution for you.
The phono cartridge, apart from some very high output moving magnets, needs a method of changing the low output of the cartridge to a higher one - the phono stage (PS). The decent phono stages also act as a filtration system for unwanted noise. So, you need one!
As above, on ebay, you can find various examples from the cheap 'n' cheerful versions from Project, NAD and Cambridge to the 'just above budget' like the Creeks, onto the pretty hot with the likes of the Michell ISO. You run the TT's output cable into the Phono stages input, then run another cable from the PS's output to the AUX (or whatever inputs free) on the receiver.
There are plenty of quality TT's on ebay such as the Rega Planer 3's for example, that will be more than satisfactory, and contrary to the above
, give a sound quality that will easily fit in with what you expect from the rest of the system.
However, as above, you need to check the condition of the LP's, and tell us how many you have inherited before you start splashing the cash. There is no point in going nuts for only 50 or so LP's in poor condition. In fact, if the condition is poor I wouldn't bother period - unless you can get access to a PC and burn them to that.
Once you get back to us with that info, and a strict budget, we can start giving firm suggestions.