Very state specific question that will require a PA practicioner to answer. You already have a public defender assigned to your case, why don't you ask them? Or contact and hire a local attorney.
Although no one can ethically provide you the advice you seek because you are represented by counsel, this answer is simply to provide information:
In York County, the ARD program does include costs totaling over $1500.00.
A 586 related to Rule 586 of the Pennsylvania Rules of Criminal Procedure which provides that a charge may be dismissed upon satisfaction. In other words, if you pay the victim, the charge can be dismissed. The victim must be in agreement.
Court costs are higher for trial than they are for a guilty plea hearing (which is generally where a 586 disposition is put before the court.
Most importantly, you should ask your PD these questions. Although they are often overburdened due to a large caseload, the attorneys in the York County District Attorney's Office are good attorneys well-versed in the law and procedures unique to the county. Call your PD and ask for a phone call in return. A few minutes may save you a lot of worry.