You will need to call your local Dell office and ask for "Spare Parts". Dell doesn't support post-purchase upgrades on internal components that aren't considered user-replaceable -- so yes, your upgrade WILL void the warranty. Since panels are not universally interchangeable, and on a model this new - you may want to consider returning the system and re-ordering if you do not find the existing panel satisfactory.
There may or may not be an IPS panel available for the model you have -- Dell will likely be the only place to find out.
Dell won't install the part - you're free to do so, but remember - you will void the warranty on the system by doing so.
The only way to upgrade a screen is at purchase -- Dell doesn't support post-purchase screen upgrades.
It likely is - before you buy it. Once purchased, Dell does not support internal part replacements (other than customer-replaceable parts - essentially memory and hard drive).
@ejn63 That statement you made is completely false. The FTC has said that manufacturers cannot void your warranty if you fix or replace parts yourself, unless they find the part you fixed or replaced is responsible for damage that would be covered under warranty. The FTC said this practice is illegal unless the item costs less than $5. You can replace any part of your laptop with any part from any place and your warranty is still valid on the original DELL parts, the parts you replace would be warrantied by the manufacturer of the new part, and if DELL tells you otherwise they are breaking the law.
"Provisions that tie warranty coverage to the use of particular products or services harm both consumers who pay more for them as well as the small businesses who offer competing products and services."